1. Field of the Invention
This invention relates to a pumpable cationic fatty alcohol dispersion having a high content of dispersed fatty alcohol and a low content of cationic dispersant.
2. Statement of Related Art
The production of numerous liquid, aqueous and emulsion-form skin-care and hair-care preparations involves the use of fatty alcohols which, in dispersed form in these preparations, provide the skin with a smooth and supple surface and the hair with improved combability and softness. The incorporation of the fatty alcohols, which are solid wax-like substances at normal temperature, requires melting and uniform, stable dispersion in the similarly heated solution or emulsion of the other components. This procedure involves considerable technical outlay, and therefore it would be of considerable advantage for many manufacturers of cosmetics if the fatty alcohol were available in the form of a stable dispersion concentrate which could be added to the preparations without heating and without any need to use special dispersion units, and could be uniformly dispersed therein simply by stirring.
It would be particularly advantageous to prepare aqueous fatty alcohol dispersions at as high a concentration of fatty alcohol content as possible while at the same time maintaining the stability of the dispersion and maintaining a viscosity which will permit the dispersion to be pumpable at ambient temperatures, i.e., at Brookfield viscosities of 0.5 to 10 Pascals as measured with a #5 spindle at 20.degree. C.
It is known in the art that cationic surface-active compositions may be used to stabilize aqueous dispersions containing fatty alcohols. For example, German patent document DE 3440935 discloses aqueous hair care preparation compositions containing a mixture of coconut fatty acid mono-ethanolamide, from 0.4 to 10% by weight of at least one linear C.sub.14 to C.sub.18 fatty alcohol and 0.1 to 1.5% by weight of a quaternary ammonium and/or pyridinium organic compound. Similar quaternary ammonium compounds, particularly lauryl, myristyl, cetyl and stearyl trimethylammonium bromides, are known to have anti-bacterial properties when used in cosmetic preparations also containing fatty alcohol dispersions, such as disclosed by G. T. Baley, G. E. Peck and G. S. Banker, J. Pharm Sci, 68, pp 696-600 (1977).
It would normally be expected that as the amount of the fatty alcohol content of aqueous dispersions is increased and the viscosity increases, a concomitant increase in the content of cationic surface-active ingredient, e.g., the quaternary compound, would be required to maintain the dispersion in a readily flowable and pumpable state.
It has been surprisingly discovered in accordance with the present invention that stable aqueous concentrates having high fatty alcohol contents of greater than 10% by weight, for example 15-25% by weight, are rendered more pumpable and have lower viscosities where the amount of cationic surface-active agent is reduced rather than increased.